Hydrogen bonds between sexual hormones and nucleobases: NMR investigations.

نویسندگان

  • W Schimmack
  • W Lohmann
چکیده

The hydrogen-bonded complexes of 17a-ethinyl-estradiol, progesterone, and testosterone with adenineand uracil-derivatives have been investigated by means of nuclear magnetic resonance (NMR) spectroscopy using deutero-chloroform as a solvent. The thermodynamic and NMR-parameters (equilibrium constant K, enthalpy AH, entropy AS, and relative chemical shift of the com­ plexes A8C) for selfassociation and mixed association have been determined. The strongest complex was formed by the phenolic hydroxyl group of estradiol with dimethyl-adenine (K = 14 mole1 , — A H = i kcal/mole, — ZlS = 8 cal/mole-grad). The values were considerably less for the OH-17 group of estradiol and testosterone. The interaction of the keto groups of progesterone and testo sterone with nucleobases was very weak: K < 1 .0 mole1 . The biological importance of these results is discussed.

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عنوان ژورنال:
  • Zeitschrift fur Naturforschung. Teil C: Biochemie, Biophysik, Biologie, Virologie

دوره 28 9  شماره 

صفحات  -

تاریخ انتشار 1973